The present invention relates generally to containers for retaining, protecting and displaying produce and methods for making such containers. In particular, the present invention relates to a produce container having an open top formed from corrugated paperboard material and useful in shipping and displaying perishable produce.
Flat sheets of corrugated paperboard, typically referred to as blanks, have been used for many years as the starting material to form produce containers. Corrugated paperboard generally refers to a multi-layer sheet material comprised of two sheets of liner bonded to a central corrugated layer of medium. Given a basic size requirement specified by the customer, industry standards, and the preference for low cost, paperboard container manufacturers strive to provide structural stacking strength with a minimal amount of corrugated paperboard. A typical well-known container is a single-piece tray design having a bottom wall, two side walls and two end walls each hinged to the bottom wall. Typically, a single piece of corrugated paperboard will be cut and scored to form a flat blank that will then be erected into this container.
Typical containers for the support and transport of food produce articles are corrugated containers having fixed configurations. These containers can be unstable when stacked and are prone to toppling. Many containers are not durable and flexible enough to protect and prevent damage to the produce. Furthermore, the side and bottom walls of produce containers are susceptible to buckling and twisting, leading to damage to the produce.
A packed container of produce will generally hold a weight suitable for handling by an individual. Such containers will be generally rectangular and have a variable height dimension. Further, these containers will normally be stacked for transport and storage. The cost of labor, in the form of the time required to handle the produce and to assemble the shipping containers, can be a significant factor in the overall cost of the produce. Many current produce containers can only be assembled by hand, a method that is costly and time consuming. Assembling paperboard containers for set-up by a machine where cooperating adjoining paperboard sections are adhesively bonded to form the produce container can reduce cost and time.
It is important in the production, distribution and sale of perishable and nonperishable articles such as produce that the articles are safely and conveniently stored for transport and safely and securely shipped for sale. Safe and secure storage and shipping is particularly a problem if heavy items must be placed in containers that are stacked upon each other. Stackable produce containers often acquire, for example, bulging side or end walls, deformed bottom walls, or smashed corners that damage the produce due to, for example, the weight of or movement of the produce during shipment. Further, if the environment in which the paperboard container is shipped or stored is refrigerated, the moisture present in a refrigerated environment is likely to be absorbed by and weaken the container.
Once the produce reaches a retail destination, the produce container is normally placed directly on display for consumer sale. This allows retailers to preserve time and money by not having to transfer produce into an alternative selling container. If a produce container arrives to a retailer in a crushed or damaged state, however, the retailer usually cannot, for aesthetic purposes, exhibit the produce container.
Vertically oriented corrugation fibers within a produce container are typically stronger and more secure than horizontally orientated fibers. Without structural rigidity, containers at or near the bottom of a stack of produce containers could buckle under the weight of the containers stacked above them. Generally, the end walls of a produce container contain vertically orientated corrugation fibers. Thus, it is preferable for the end walls to contain as few openings as possible. Optimal cooling efficiency, which enhances produce quality and shelf life, is also desirable. Cooling is achieved by including openings in each end wall to allow cool air flow from one end of the container to the other.
Thus, it is desirable to provide a container for transporting produce that is both durable and secure to prevent corrugation failure and produce damage and yet allows sufficient air flow to achieve optimal cooling efficiency.
Accordingly, an object of the present invention is to provide a produce container featuring superb stacking strength and resistance to forces encountered in shipping that tend to weaken standard produce containers. Another object of the present invention is to provide such a produce container that is cost-effective and easy to manufacture.
These and other objects are realized by a produce container comprising a bottom wall and a plurality of side walls. The corners where the side walls meet are comprised of multiple layers of vertically corrugated reinforcement flaps. The corners further contain shoulders attached to a side wall and a reinforcement flap at each corner. The shoulders prevent nesting of stacked containers and extend across a portion of the top of the container, running generally parallel to the bottom wall.
To further lend structural strength to the container, a plurality of side walls feature partial rollovers along their top edges. These partial rollovers comprise a major flange, which is cut around a center flange. The center flange is first folded about one axis down toward the side wall and the major flange is then folded about a second axis so as to capture the center flange between the major flange and the side wall. The folding axis of the major flange corresponds to the tops of a plurality of simultaneously-formed doubled indexed stacking tabs.